Potential in autumn-sown white clover says Lincoln

Press, 10 December 1982, Page 22

Potential in autumn-sown white clover says Lincoln

Although Lincoln College's first attempt at autumn establishment of white clover for seed production after a cereal crop is not looking too good, the technique has potential. Visitors who attended a farm walk over the college's cropping farm last week were told that autumn sowings of clover should be made no later than the middle of February and there should be moisture available.

Because of delays and a very dry autumn, the college’s clover was not sown until March 30. Mr Graham Tate, senior lecturer in Rural Extension at Lincoln and supervisor of the cropping farm, told the field day that the clover should be “motoring” into the

winter so it could withstand the climate.

The college’s autumn clover was at present weedy and not of the standard wanted, but Mr Tate said a lot had been learned about the technique. The college normally established white clover by undersowing with a cereal crop, but this method has several disadvantages. If there was a good crop of wheat, then the undersown clover was usually a poor crop. Without undersown clover, cereal straw could be burned which could help reduce the build-up of disease, and it was easier to treat hard-to-kill wppds Mr Peter Clifford of the Grasslands Division of the D.S.I.R. at Lincoln, said part of the reason for this year's poor crop of autumn-sown clover was attributed to the delay caused by the joining together of two paddocks and the dry autumn. In spite of this the crop is expected to yield about 300 kg per ha. Future crops are likely to be better. Mr Clifford has been doing

autumn-sown clover trials for eight years and the yields have never been below 800 kg per ha. To get the best from autumn sowings, Mr Clifford suggested several points:— <9 Sowings should be made before mid-February, particularly in shorter autumn establishment areas nearer the mountains. ® Every second coulter set at 3kg per ha was satisfactory for stronger lowland, but skg per ha at standard row spacings could be necessary where sowing was delayed or the autumn establishment period was shorter. 0 Apply 150 kg per ha of superphosphate or serpentine super at sowing. 0 Where frost heave was likely to be a problem, 3 to skg per ha of annual ryegrass or 8 to 10kg per ha of cereal should be included. ® If intending to use direct drill or minimum tillage sowings, straw choppers and spreaders should be used on the header. This approach was best used for short straw crops; tall crops should be baled or burned. © Direct drill if suckling

clover was likely to be a problem. © Irrigation would be needed at least three years in five. Irrigation should be used before working or sowing to ensure a good weed strike. © Autumn sown crops were more susceptible to winter application of 2.4-D ester. ® Paraquat . used in August-September gave good general weed control. Light grazings only should be practised where required to control competition from other species. 0 In seasons where plant development was limited, closing the paddocks to flower up to one month earlier than for traditional spring sowings could be necessary to maximise seed yields. Visitors also looked at clover sown by traditional methods and these paddocks were looking good. Yields were estimated at 700 kg per ha. Hot north-west winds had caused acute moisture stress in the wheat crops. A paddock of Rongotea which was

drilled in early May was looking a picture after the Labour Weekend rainfall, but recent hot weather had severely stressed the crop. Signs of stripe rust appeared near the end of September and the crop was sprayed in the middle of October. The infection was starting to build up again and would need spraying. The farm had decided to give tick beans another go after obtaining a yield of 2.2 tonnes per hectare last year. This was described by Mr Tate as about par for the course. The beans were drilled at the end of April in a paddock usually regarded as wetter than the others, but the winter had been dry. A great yield was not expected this year. Tick beans are coming into prominence as a winter green feed for stock. This year the college farm has 68ha in wheat (95 last year); barley, 12ha (17ha); white clover seed. 86ha (52ha); freezing peas, 33ha (29ha); tick beans, 7ha (7ha); Maku lotus. 3ha (3ha); and fodderbeet, sha (IQha).